Although semiconductor light emitting devices for illumination require monochromatic light emission in some cases, basically, white light near sunlight is needed. White semiconductor light sources include primary color (RGB) device arrays, pseudo-white light sources using a color mixture from a blue light emitting device and yellow light produced by self-excited light emission at substrate defects of the blue light emitting device, primary color fluorescent material excitation light sources using ultraviolet light emitting devices, and the like (for example, JP-A 2007-243054 (Kokai), JP-A 2008-112867 (Kokai), and JP-A 2006-339060 (Kokai)).
For such semiconductor light emitting devices, technology is known for removing a light emitting device substrate used during crystal growth such as JP-A 2004-284831 (Kokai), Pioneer R&D, 2000, Vol. 12, No. 3, p. 77, and the like. Known technology for sealing functioning devices in the wafer form includes Electronic Components & Technology Conference, 2008, p. 824 and the like.
In the case where semiconductor light emitting devices are utilized as illumination to replace incandescent lightbulbs and fluorescent lamps, a relatively high light output is necessary. Therefore, insufficient heat dissipation of the semiconductor light emitting device easily causes the undesirable deterioration of the sealing resin protecting the semiconductor light emitting device.
The life of a semiconductor light emitting device itself is much longer than that of an incandescent lightbulb. The main causes of the semiconductor light emitting device becoming unusable may include oxidization, deterioration, and overheating of the metal of the electrode portions, shorts of gold wire in the interior due to shocks, etc. Product life refers to the point when the ability to transmit light drops due to deterioration of the sealing resin and the amount of light emission falls below a constant level. In particular, the resin in components using fluorescent material excitation by a light emitting device emitting blue to ultraviolet light easily deteriorates due to the heat from the exciting device and the ultraviolet rays; and it is difficult to realize high output and long life.
In package structures in which a light emitting device chip is mounted on a substrate of silicon and the like, thinner substrates are desirable due to the need for good heat dissipation, flexibility, etc. However, limitations are encountered when making the entire surface of the substrate thinner from the aspects of ease of handling, reliability, and the like.